The present invention relates to a printing state automatic switching apparatus and method which automatically switch the printing state of a printing press from a first printing state to a second printing state.
Along with diversification of printing, various kinds of sheet-fed offset printing presses equipped with a convertible press mechanism have been proposed and put into practical use. A single sheet-fed offset printing press equipped with a convertible press mechanism can selectively perform single-sided printing and double-sided printing. Reference 1 (Japanese Patent Laid-Open No. 10-58654) and reference 2 (Japanese Patent Laid-Open No. 4-85041) describe examples.
A conventional sheet-fed offset printing press equipped with a convertible press mechanism displays the progress of automatic switching from a single-sided printing state to a double-sided printing state, automatic switching from a double-sided printing state to a single-sided printing state, or automatic change of the paper size in a double-sided printing state. If something unusual occurs during an operation, an operator manually returns the mode to the single-sided printing state while checking the display.
For this reason, the conventional sheet-fed offset printing press equipped with a convertible press mechanism requires an enormous labor and a very long time to return to the single-sided printing state. Additionally, the operation of returning to the single-sided printing state is very complex. Any operator of the print shop cannot do the operation. Instead, the shop must request the maker of the printing press to dispatch a serviceman for the operation. It is impossible to print during that time, resulting in very low level of capacity utilization.